KABUL â A massive blast Wednesday tore through the diplomatic quarter of the Afghan capital of Kabul killing at least 80 people, according to officials, underlining the fragility of the country as it buckles under a wave of rebel attacks.

The Interior Ministry said the blast was triggered by huge quantity of explosives hidden in a water tank that went off during the peak of the morning rush hour on a busy road in Wazir Akbar Khan area of the city.

Wahid Majroh, spokesman of the Health Ministry, said at least 350 people were also wounded.

âI felt like it was an earthquake and after that I do not know what happened,â said Mohammed Hassan, 21, who had been attending a bank training program. âAll the staff around me, everyone, was injured.â

Afghanistan has been suffering from a surge of attacks from the Taliban movement since it declared a new spring offensive, including spectacular attacks on the once secure capital.

There have also been a string of attacks claimed by the rival Islamic State group.

Even by the standards of war-torn Kabul, however, this blast stood apart for its sheer magnitude, blowing out windows across the city and setting dozens of cars ablaze.

The target was unclear, but the bomb went off near the Germany Embassy and the nearby French and Chinese embassies were reportedly damaged, according to Reuters news agency.

Officials said, however, that most of the casualties were civilians.

âThese heinous acts go against the values of humanity as well values of peaceful Afghans,â said a government statement. âThese attacks also demonstrate the extreme level of atrocity by terrorists against innocent civilians.â

More than three hours after the blast, ambulances were still rushing to the site and its smoking, wrecked buildings to evacuate the casualties, a sign that the number of dead and wounded could still rise.

Authorities closed all key roads to traffic to deal with the aftermath of the blast and as a precautionary measure in case further explosions were planned.

At Wazir Akbar Khan hospital, not far from the blast, hundreds of anxious and angry people crammed outside the main entrance, trying to get inside to see their injured loved ones, while police guarded the facility. Ambulances rushed back and forth carrying the injured, the dead, and sometimes just body parts burnt black by the blast.

Police and medics carried gray body bags covered with blood.

Like past attacks, the anger soon moved to the government for failing to protect residents â even in one of the most guarded enclaves in the city.

âThis is an inept government that cannot protect the people and must be dissolved. It is time for an interim government to be formed,â said lawmaker Mirwais Yasin.

There are already 8,000 U.S. troops in Afghanistan supporting the government, but earlier this year, their leader, Gen. John Nicholson, said he needed several thousand more to break the stalemate.